An oxygen (O2) sensor is an electronic device that measures the proportion of oxygen (O2) in the exhaust gas of an internal combustion engine. It is used to optimize the air-fuel ratio of the engine, which is important for both performance and emissions.
O2 sensors are typically located in the exhaust manifold or exhaust pipe, and they work by measuring the difference in oxygen content between the exhaust gas and the ambient air. This difference in oxygen content is then used to calculate the air-fuel ratio of the engine.